CN111655574B

CN111655574B - Internally detachable retractable propeller for marine vessel and marine vessel

Info

Publication number: CN111655574B
Application number: CN201880086760.5A
Authority: CN
Inventors: V·克劳斯; E·斯内尔德斯
Original assignee: Wartsila Finland Oy
Current assignee: Wartsila Finland Oy
Priority date: 2018-01-17
Filing date: 2018-01-17
Publication date: 2022-03-18
Anticipated expiration: 2038-01-17
Also published as: KR102396228B1; CN111655574A; KR20200105484A; WO2019141354A1

Abstract

The invention discusses an internally detachable retractable thruster for a marine vessel, the thruster (8) comprising a propeller (12), a thruster body (14), means (18, 22, 54) for driving and steering the propeller (12), means for moving the propeller (12) in a vertical direction between its top and bottom positions, means (24) for guiding the vertical movement of the propeller (12), and a sliding frame (32) supporting the means (18, 22, 54) for driving and steering the propeller, the sliding frame (32) being movable along the vertical movement guide means (24), the vertical movement guide means (24) being fastened to the frame, the frame comprising an upper frame (28) and a lower frame (30), the vertical movement guide means (24) being arranged between the upper frame and the lower frame, wherein the lower frame is a thruster basin (30), the propeller tub (30) at least partially houses, when in operation, a sliding frame (32) and means (22, 54) for driving and steering the propeller (12) arranged in connection with the sliding frame (32).

Description

Internally detachable retractable propeller for marine vessel and marine vessel

Technical Field

The present invention relates to an internally removable retractable thruster. The invention also relates to a marine vessel.

Background

Marine vessels use various propulsion systems or units. The main propulsion unit(s) is/are typically arranged at the rear of the vessel. The main propulsion unit may be a stationary propeller arrangement generating thrust in the longitudinal direction of the marine vessel, or it may be a pod or a propeller, i.e. a propeller arrangement that is rotatable about a vertical axis.

Marine vessels also have other propulsion means mainly used in manoeuvring ships, barges, ferries etc. e.g. in harbours. One type of such propulsion device is a tunnel thruster, which may be used at the bow and stern of a ship. The tunnel thruster is arranged in a horizontal tunnel extending through the hull of the marine vessel transversely to the longitudinal direction of the marine vessel in order to assist in moving the entire vessel or one end of the vessel sideways, for example for docking purposes.

By making these units retractable, thrusters have been developed further, i.e. the thruster can remain within the hull, but the thruster can also be lowered below the hull, i.e. below the baseline of the marine vessel. When the thruster is in the lowered position, the thruster may be rotated about a vertical axis, and the thruster may thus be used to generate thrust in any desired direction for steering purposes. Such thrusters are typically used for dynamic positioning purposes and to maintain the vessel in a fixed orientation relative to the prevailing wave and current direction. However, when sailing to a working position or entering a port, the positioning thrusters are retracted horizontally flush with the keel of the vessel in order to reduce the water resistance and not interfere with the seabed in shallow waters. However, such thrusters are often relatively difficult to inspect and maintain as this can only be done by using divers or by dry docking the vessel.

US6,375,524 may be discussed as an example of a prior art retractable thruster that solves the above mentioned problems. This us patent discusses a marine vessel provided with a vertical shaft in which the propeller is placed and at which the propeller can be retracted from its operating position below the keel level of the vessel to two upper positions. The first lower position is a position in which the thruster is held while underway and the second upper position is a position in which the thruster can be inspected and maintained. For such operations to work, the marine vessel needs a vertical shaft or propeller well, and the propeller needs to be provided with a frame supporting the propeller and its drive equipment and connected to the well so that the propeller can move in the vertical direction. In other words, the thruster may be mounted in the thruster well from the deck of the marine vessel, i.e. from above. Thus, there is no need to use divers or dry dock marine vessels in any installation or maintenance operations associated with the thruster.

The above-mentioned us patent shows how a thruster well is formed of two parts. The first section extends from the keel level of the marine vessel above a specified intermediate deck level. The first portion of the thruster well has a first diameter which allows the tubular thruster frame to be lowered in the first portion, leaving a small gap between the thruster well and the thruster frame. At some point along their length, both the well and the frame are provided with sealing rings which, when facing each other, seal the gap. Above the intermediate deck, the thruster well has a larger diameter, so that lifting equipment for the thruster can be arranged there, and also room is left for maintenance personnel. The intermediate deck is shown below the water line so that if water is allowed to fill the thruster well, the intermediate deck will also be submerged. To prevent this from happening, the first part of the thruster well extends above the intermediate deck such a vertical distance that the thruster well extends above the waterline.

The propellers of the above-mentioned us patents fulfill all the basic requirements set to an internally mountable retractable propeller. However, the propeller frame presents a problem because it is a tubular housing covering all propeller parts except the propeller itself, i.e. the rotary drive unit is inside the tubular frame, whereby access to the drive unit is complicated. If the pusher is not so large that a person can fit into the tubular frame, the pusher must be released from the frame to access the drive unit. Other disadvantages of the tubular frame are its size, weight and manufacture.

KR- A-1020140137850 discusses A barrel type propeller which is very close in construction to the propeller discussed in the above-mentioned us patent document. The only difference worth mentioning is that the thruster well in korean literature extends horizontally from the keel of the vessel well far above the water level so that water entering the thruster well does not cause problems. However, the propeller of the korean document has the same problem as the propeller of the united states, that is, the propeller frame is a pipe, and thus the rotary drive unit cannot be directly accessed for repair or maintenance.

EP-a1-2995549 discusses a retractable propeller disposed in an upwardly extending cavity formed in the bottom of the hull of a marine vessel. The impeller includes a cylindrical first housing extending through a cylindrical opening at the top of the cavity. The cylindrical opening is provided with bearings and seals for supporting and sealing the first housing with respect to the vessel hull. The propeller also includes a second housing attached to a lower end of the first housing. The second housing houses a vertical shaft, a horizontal shaft and a transmission for driving the propeller. A lifting device is arranged in the hull of the vessel above the top of the cavity for lifting and lowering the first housing. In other words, the EP document does not discuss internally removable thrusters, but thrusters that have to be installed in their cavities from below, whereby also their repair and maintenance cannot be carried out inside the hull of the marine vessel.

The object of the present invention is to optimize the frame structure of an internally detachable retractable thruster so that the various thruster components are easily accessible without major disassembly operations.

Another object of the invention is to reduce the weight and manufacturing costs of the propeller frame.

Disclosure of Invention

The above and other objects of the invention are met by an internally detachable retractable thruster for a marine vessel, the thruster comprising a propeller, a thruster body, means for driving and steering the propeller, means for moving the propeller in a vertical direction between its top and bottom positions, vertical movement guiding means for guiding the vertical movement of the propeller, and a sliding frame supporting the means for driving and steering the propeller, the sliding frame being movable along the vertical movement guiding means, the means for driving and steering the propeller comprising a drive shaft surrounded by a steering tube, the vertical movement guiding means being fastened at their upper ends to an upper frame and at their lower ends to a lower frame, the upper frame being fastened to a supporting hull structure, and the lower frame is a thruster basin formed by a basin bottom with an opening for a steering pipe, a basin wall extending upwards from the basin bottom and a basin flange, the opening being provided with a seal, the thruster basin at least partly accommodating the sliding frame and the means for driving and steering the propeller arranged in connection with the sliding frame when the thruster is in an operating position with its propeller and thruster body located below the keel level of the marine vessel.

The present invention also brings about a number of advantages when solving at least one of the above-mentioned problems, some of which are listed below:

the thruster may be lifted and dismantled internally for maintenance purposes. This avoids the costs and risks associated with underwater disassembly, or alternatively avoids the need for the vessel to enter dry dock,

the structure of the propeller is less complex and lighter,

the thruster parts are easily accessible without the need to release the thruster from its frame.

It is to be understood, however, that the listed advantages are merely optional and, thus, depending upon the manner in which the invention is practiced, one or more of the advantages may be achieved.

Drawings

The inner detachable retractable thruster of the present invention will be described in more detail with reference to the accompanying drawings, in which

Fig. 1 shows a partial vertical cross-sectional view along the longitudinal centre line of a marine vessel, which is provided with an internally detachable retractable thruster according to a preferred embodiment of the invention,

fig. 2 shows a vertical cross-sectional view of the internally detachable retractable thruster of fig. 1, positioned in a sailing position inside the hull of a marine vessel,

FIG. 3 shows a vertical cross-sectional view of the internally removable retractable thruster of FIG. 1 positioned in an operating position below the keel level of the marine vessel, and

fig. 4 shows a vertical cross-sectional view of the inner detachable retractable thruster of fig. 1 lifted above its sailing position, i.e. in its maintenance, repair, installation or removal position.

Detailed Description

Fig. 1 shows a partial vertical cross-sectional view along the longitudinal centre line of a marine vessel 2, which marine vessel 2 is provided with an internally detachable retractable thruster 8 according to a preferred embodiment of the present invention. This embodiment shows an internal removably retractable thruster 8 arranged at the bow of the marine vessel. However, in practice, the retractable thruster may be applied at any longitudinal position along the length of its hull. The figure shows the thruster 8 positioned in a vertical thruster well formed by a lower thruster well 10' and an upper thruster well 10 "extending from the deck 4 of the marine vessel 2 all the way to its keel level KL. The internally detachable retractable thruster 8 is shown in its operational position below the keel level KL of the marine vessel 2, the thruster well being in principle formed of two parts. The lower propeller well 10' is mainly positioned below the waterline WL and starts from the keel level KL, i.e. at the bottom of the marine vessel 2, and extends above the waterline WL. Depending on the marine vessel, the upper thruster well may be a series of closable openings one above the other in the deck of the vessel, or a tubular well arranged in a vertical direction through the deck of the vessel. There may be a cavity between the upper and lower thruster wells, which cavity may be applied for example for service and maintenance thrusters.

Fig. 2 shows a vertical cross-sectional view of the internally detachable retractable thruster positioned in sailing position inside the lower thruster well 10' inside the hull of the marine vessel of fig. 1. The retractable thruster 8 is mainly formed by a thruster propeller 12, its right-angle gear arranged within a thruster body 14 of the propeller 12, a nozzle ring 16 surrounding the propeller 12 and connected to the thruster body 14, a drive shaft 18 surrounded by a steering tube 20, an electric drive motor 22 arranged at the upper end of the drive shaft 18 in the embodiment shown, means (not shown) for moving the thruster 8 between a top position and a bottom position of the thruster 8, and upper and lower guide means 24, 26 for supporting the inner detachable retractable thruster when the thruster is moved in a vertical direction. At this stage, however, it should be understood that the drive shaft and the electric motor may be replaced by an electric or hydraulic drive unit arranged on the same axis as the thruster propeller 12, which is connected to the thruster body 14. In this case, only the necessary electrical wires and/or hydraulic pipes need to be led down to the thruster body 14.

The retractable thruster 8 is fastened at its upper end to the intermediate deck 6, or more generally to the supporting hull structure (these cover all beams, walls, decks, stiffeners etc. arranged in the hull of the marine vessel) by means of an upper frame 28. At least two vertical guide bars 24 are fastened at their upper ends to an upper frame 28 and at their lower ends to a lower frame, i.e. a propeller basin 30. The sliding frame 32 is arranged in connection with the guide bar 24 such that the sliding frame 32 can slide vertically along the guide bar 24. The slide frame 32 supports the drive motor 22 and is connected by means of the steering tube 20 to a thrust beam 34 located below the thruster basin 30. The drive shaft 18 extends through the steering tube 20 down to the propeller body 14. The thrust beam 34 is rotatably disposed to the lower end of the steering tube 20. The steering tube 20 is rotatably supported to the slide frame 32 at its upper end and attached to the propeller body 14 at its lower end. Rotation of the steering tube 20 and subsequent steering of the propeller 12 is accomplished by a rotating gear 54 (fig. 3). The thrust beam 34 extends substantially horizontally towards a wall 36 of the lower propeller well 10'. The wall 36 is provided with vertical guides 26 with which the ends of the thrust beams 34 are arranged in sliding communication. In other words, the vertical movement of the pusher is ensured by the guide bar 24 at the upper end of the pusher 8 and the guide rail 26 at the lower end of the pusher 8. The thrust beams 34 and the guide rails 26 transfer the thrust of the propeller first to the wall of the lower propeller well 10' and then further to the hull of the marine vessel.

The wall 36 of the lower propeller shaft 10' forms a cavity in which the propeller 12, the propeller body 14 and the nozzle ring 16 (if used) are received when the propeller 12, the propeller body 14 and the nozzle ring 16 are not in operation. The height of the wall is typically slightly greater than the diameter of the propeller 12 or nozzle ring (if used). In case the waterline WL of the marine vessel extends above the wall 36 of the lower propeller well 10', the wall 36 is provided with a substantially vertical wall extension 38 to raise the height of the wall above the waterline WL. Wall extension 38, which extends upwardly from deck 40 (typically the lowermost deck, but sometimes the deck or a second deck above the lowermost deck), may be an integral part of wall 36 to which rail 26 is secured, or as a separate wall member secured to wall 36 or deck 40 in a waterproof manner. When the thruster is installed in the lower thruster well 10 ", the thruster basin 30 is located inside the wall extension 38. The propulsor basin 30 is formed from a basin bottom 42 (i.e., base plate), a basin wall 44, and a basin flange 46. A basin wall 44 extends upwardly (preferably, but not necessarily, vertically and at a right angle) from the basin bottom 42. The bowl flange extends outwardly from the bowl wall 44. The basin flange 46 is preferably, but not necessarily, positioned to an upper edge of the basin wall 44, and preferably, but not necessarily, extends radially outward from the upper edge. The horizontal cross-section of the propeller basin 30 is preferably, but not necessarily, circular, but square, rectangular and the like are also contemplated, if desired. In a similar manner, the horizontal cross-section of lower propeller well 10' is preferably, but not necessarily, circular, but square, rectangular and similar shapes are also contemplated, if desired. The basin flange 46 is arranged to rest on an upper edge 48 of the wall extension 38. A seal is provided between the basin flange 46 and the rim 48 of the wall extension 38. The basin bottom 42 is provided with an opening 50 for the steerer tube 20. The opening 50 is provided with a seal 52 for preventing water from entering the interior of the basin 30.

Fig. 3 shows a vertical cross-sectional view of the inner detachable retractable thruster of fig. 1 and 2 positioned in an operational position with the propeller and the thruster body below the keel level KL of the marine vessel. Figure 3 reveals why a thruster well 30 is required. Now, the presence of the thruster basin 30 sealed in a watertight manner with respect to the steering pipe 20 and the wall extension 38 of the lower thruster well 10' makes it possible to bring the sliding frame 32, together with all its equipment, such as the rotary gear 54 turning the thruster body, at or even below the waterline WL. Thus, the sliding frame 32 and the propeller basin 30 are sized such that the sliding frame 32 fits within the interior dimensions of the propeller basin 30. Without the propeller basin 30, all such equipment that should not be in contact with the sea water should be arranged at a higher level, which would mean that the length of the drive shaft and the steering tube is increased. This also means that the weight of the propeller increases and, naturally, also means that the propeller takes up more space.

The required height of the basin wall 44 depends on the size of the propeller relative to the difference between the keel level KL and the water line WL. At its minimum, when the propeller is in its rest position, i.e. stationary inside the propeller well 10' in the hull of the marine vessel, the space required by the propeller body 14, the propeller 12 and the nozzle ring 16 in the vertical direction is slightly larger than the diameter of the propeller or the nozzle ring.

Fig. 4 shows a vertical cross-sectional view of the inner detachable retractable thruster of fig. 1 lifted above its sailing position, i.e. in its service and maintenance position or its fully installed or detached position. The figure also shows the importance of the wall extension 38, i.e. even if there is nothing to prevent sea water from entering the lower propeller shaft 10', the deck 40 is not occupied by sea water since the wall extension extends above the waterline WL. The wall extension 36 also provides the possibility of mounting the cover 56 on the edge of the wall extension 38 and on the seal on the edge, so that the lower propeller well 10' is covered again and the cover 56 can be used as a support surface for servicing the propeller or propeller body.

Fig. 4 also shows the preferred dimensions of the extension wall, as follows: according to a preferred embodiment of the invention, the required height of the propeller well 10', i.e. the height of the wall 36, is about 1.1 to 1.5 times the diameter of the propeller or the nozzle ring. If the waterline WL extends higher, a wall extension 38 to the wall 36 of the lower thruster well 10' is required, as shown. For example, if waterline WL has a height H1 from keel level KL and deck 40 has a height H2 from keel level KL, wall extension 38 has a height H that is greater than H1-H2, preferably about at least 1.2 times H1-H2, more preferably about at least 1.5 times H1-H2.

It should be understood that the above is merely exemplary of the novel and inventive inner detachable retractable pusher. It should be understood that although the above description discusses a certain type of retractable pusher, the type of retractable pusher does not limit the invention to the type in question. It is therefore clear that the driving of the propeller can be arranged by means of an electric, hydraulic motor arranged below in the thruster body or a diesel motor in a Z-drive configuration. Furthermore, it is clear that the shape of the nozzle ring does not limit the invention, wherein the ring may be cylindrical or conical. The above description should not be taken as limiting the invention in any way, but the full scope of the invention is defined only by the appended claims. From the above description it is understood that individual features of the invention may be used in combination with other individual features even if such a combination is not specifically shown in the description or the drawings.

Claims

1. An internally detachable retractable thruster for a marine vessel, the thruster (8) comprising a propeller (12), a thruster body (14), means for driving and steering the propeller (12), means for moving the propeller (12) in a vertical direction between its top and bottom positions, vertical movement guide means (24) for guiding the vertical movement of the propeller (12), and a sliding frame (32) supporting the means for driving and steering the propeller, the sliding frame (32) being movable along the vertical movement guide means (24), the means for driving and steering the propeller (12) comprising a drive shaft (18) surrounded by a steering tube (20), characterized in that the vertical movement guide means (24) are fastened at their upper ends to an upper frame (28) and at their lower ends to a lower frame, the upper frame is fastened to a supporting hull structure and the lower frame is a thruster basin (30), the thruster basin (30) being formed by a basin bottom (42), a basin wall (44) extending upwards from the basin bottom (42) and a basin flange (46), the basin bottom (42) having an opening (50) for the steering tube (20), the opening (50) being provided with a seal (52), the thruster basin (30) at least partly accommodating the sliding frame (32) and the means for driving and steering the propeller (12) arranged in connection with the sliding frame (32) when the thruster is in an operational position with its propeller and thruster body below the keel level of the marine vessel.

2. The internally detachable retractable thruster of claim 1, wherein the steering pipe (20) is mounted to extend through the opening (50), the steering pipe (20) being rotatably supported to the sliding frame (32) at its upper end and attached to the thruster body (14) at its lower end.

3. The internally detachable retractable thruster of claim 1, wherein a thrust beam (34) is rotatably arranged at the lower end of the steering pipe (20) below the thruster basin (30).

4. The internally removable retractable thruster of claim 1, wherein the basin flange (46) extends outwardly from the basin wall (44).

5. A marine vessel comprising the internally detachable retractable thruster (8) of claim 1, the marine vessel (2) having a lower thruster well (10 ') with a vertical wall extension (38) having an upper edge (48) positioned above a Waterline (WL) of the marine vessel (2) when the marine vessel is in a sailing condition with the thruster positioned in the lower thruster well (10') inside the hull of the marine vessel, the thruster basin (30) being supported on the upper edge (48) and sealed with respect to the upper edge (48) when the thruster is in a sailing position and an operating position.

6. Marine vessel according to claim 5, characterised in that a cover (56) is arranged over the seal and the upper edge (48) when the thruster is lifted to its service and maintenance position.

7. Marine vessel according to claim 5, characterised in that the vertical wall extension (38) is a separate wall member fastened to a deck (40) or to a wall (36) of the lower propeller shaft (10').

8. Marine vessel according to claim 5, characterised in that the vertical wall extension (38) is an integral part of the wall (36) of the lower propeller well (10').

9. Marine vessel according to claim 5, characterised in that the marine vessel has a Waterline (WL) with a height H1 from the Keel Level (KL), a Keel Level (KL) and a deck (40), the deck (40) having a height H2 from the Keel Level (KL) and the basin walls (44) having a height (H) which is larger than H1-H2.